Determination of pesticide residues in fish from agricultural areas of Santa Fe (Argentina)

MAGNI, FLORENCIA; MICHLIG, MELINA; DEMONTE, LUISINA; REPETTI, MARÍA R.

Panamá

Workshop; 9TH Latin American Pesticide Residue Workshop (LAPRW); 2023

Ministerio de Desarrollo Agropecuario de Panamá (MIDA)

Over the past decades the Province of Santa Fe, Argentina, has experienced a broad expansion of its agricultural limits due to the development of new production techniques and the use of genetically modified crops. The many chemicals used in the new agricultural systems often reach the surrounding lakes and rivers affecting the life of aquatic ecosystems, making fish the more susceptible one because of its commercial value.This work presents the optimization of a multi-residue method for the determination of pesticides in two native fish (Markiana nigripinnis and Astyanax lacustris) that inhabit the rivers surrounding rice fields. In a first stage, the analytical scope was a mixture of pesticides commonly used in rice crops (bifenthrin, azoxystrobin and cyproconazole) which was spiked in samples of the above-mentioned species that were obtained before and after fumigation [1]. In a later stage, the scope was expanded to a total of 136 pesticides in another fish species that is locally consumed and exported to other countries for human consumption, Prochilodus lineatus (sábalo) [2].Fish muscle and viscera were analyzed using a QuEChERS method with final determination of pesticides by UHPLC-ESI-MS/MS and GC-MS/MS, validated according to the SANTE guidelines. Sediments and water samples from the same sampling sites were also analyzed using the validated method and Solid Phase Extraction (SPE), respectively.Bifenthrin, azoxystrobin and cyproconazole residues were detected in sediments, waters and fish samples obtainded after the fumigation of rice fields, but not in the sample obtained before the application.In the muscle tissues of P. lineatus we found pesticides exceeding the respective MRLs such as cypermethrin (204 µg/kg) and pyraclostrobin (50 µg/kg), and in its viscera the main findings were cypermethrin (506 µg/kg), chlorpyrifos (78 µg/kg) and lambdacyhalothrin (73 µg/kg).These results evidence the need for periodic monitoring programs due to the high concentration of pesticides found and the associated potential risks for the life of these aquatic species and the humans that might eventually consume them.